The present invention relates generally to power driving mechanisms for tools and, more particularly, to apparatus and a method for driving tools of various types into earth, coal, wood, concrete, asphalt or other materials or substances.
Various forms of power sources, mechanical, hydraulic, pneumatic or others, have been used to drive tools for various purposes, for example, digging coal, cutting trees, driving piles, pavement removal, earth working, and various agricultural operations. The specific tool is designed for the particular job.
Recently, a power source has been developed employing a resonant vibration system driven by a sonic generator, an example being shown and described in U.S. Pat. No. 3,367,716. While the resonant vibration principle has merit in that considerable force can be generated, the proper transfer of such force to the material has proved extremely difficult to accomplish. The sonic generator is mounted on a tool holder or carrier that is driven by a continuous unidirectional force. A resonant force transmitting beam couples the sonic generator to a tool that is advanced intermittently along a work path responsive to the continuous unidirectional force and the force of the sonic generator. When the tool encounters an immovable object, i.e., an object that the oscillator force is unable to overcome, destruction of the tool driving apparatus has been experienced.